The present invention relates to a method for predicting the rheological properties of compositions comprising a filler in a matrix. The present invention further relates to a method of choosing a filler for a composition in order to achieve a desired rheological property.
In polymer or solvent-based compositions, other components may be added which contribute to the composition's ultimate properties. For instance, with respect to a polymeric composition, such as polyurethane, a filler or other particle is often present. However, in the past, typically the choice of a filler for a composition is not as elementary as simply picking any filler and adding it to the composition. In fact, it is known in the industry that each filler performs differently with respect to, for example, rheological properties. Thus, and strictly as an example, carbon black can be used as a filler, and it has been shown that one type of carbon black having certain properties such as a particular BET surface area, a DBP, tint strength, and the like can impart desirable rheological properties to a polymer composition while another carbon black having the same or similar physical parameters will not impart the same desirable rheological properties. Due to this phenomenon, in the industry, it was quite common to use past experiences in an effort to determine what filler would best interact with the components of a composition. However, even this strategy does not often work since, for example, various polymer compositions can differ from past polymer compositions, which results in the filler not providing the same desirable rheological properties.
Thus, it was quite common in the industry to simply use a hit and miss strategy wherein a carbon black or other filler is tested in a composition and then compared with another filler that is tested in the same composition until the desired rheological properties are achieved. This hit and miss strategy is quite costly, takes large blocks of time, and further does not result in the best filler being used to provide the most optimized rheological properties in the particular composition.
Thus, there is a need in the industry to provide a means to determine the best class of fillers for a particular compositikn in order to achieve the most optimized rheological properties for the composition.